1. Field of the Invention
The present invention relates to a process of manufacturing a ski having an upper decorated surface.
2. Description of Background and Relevant Information
Skis utilized in winter sports, for example, and adapted to slide on snow and ice, generally comprise a lower sliding surface joined to two lateral surfaces along two lower edges provided with metallic corners, the lateral surfaces being connected to an upper surface.
For aesthetic reasons, the upper surfaces, and even the lateral surfaces, are decorated. Traditionally, the decoration of the upper surface of a ski is created by a silk-screen process. However, it is more difficult to decorate the lateral surfaces. Further, the decoration is fragile and is directly exposed to shocks and attack from external sources.
Skis are known to be manufactured by a hot molding process during which thermodeformable layers of material are deformed. To ensure the protection of the decoration during such a process, an appearance layer can be utilized which is made from a sheet of thermodeformable material composed of at least one outer layer made from a first plastic material which is substantially transparent, and an inner layer made out of a second plastic material which provides a contrast and which is substantially opaque, the inner layer containing coloring agents defining a decoration which is then visible through the outer layer.
The inventors have observed that, in attempting to mold a ski comprising such a sheet of thermodeformable material having two layers, the inner layer bearing the decoration tends to deform during molding, the material tending to flow particularly adjacent the breaks, or discontinuities, in the flatness of the planar surface of the ski, such as the upper edges of the ski, which causes a deformation of the decoration and, thus, defects in appearance. At the same time, however, it is required that the upper layer perfectly mate with the mold, in particular the edges and the reliefs carried onto the surface, which are generally obtained by making the material flow within the mold.